Exhibit 99.1

Olin Updates Pension Plan Guidance

    NORWALK, Conn.--(BUSINESS WIRE)--Feb. 4, 2004--Olin Corporation
(NYSE:OLN) today updated its previous guidance concerning its pension
plan. In a press release issued on January 29, 2004, the Company
disclosed that it estimated its non-cash pension expense for the full
year 2004 would increase in the $20 million pretax range over 2003
levels and would continue to increase by about $10 million per year
over the next few years. Olin also estimated that only minimal
contributions to the plan would be required until 2006. These
estimates did not assume that the Company would make a voluntary
contribution to the pension plan.
    The Company now plans to make a voluntary contribution to the
pension plan of approximately $125 million with the proceeds from the
issuance of common stock. Olin expects the 2004 voluntary contribution
will have a beneficial effect on the 2004 pension expense of
approximately $10 million pretax ($6 million after tax). Therefore, it
is now expected that the non-cash pension pretax expense in 2004 will
be approximately $10 million higher than 2003 ($2.5 million per
quarter) and that pension expense will continue to increase by about
$10 million per year over the next few years. The voluntary
contribution will improve the funded status of the pension plan. Based
on revised assumptions and estimates taking into account the 2004
voluntary contribution, the Company now believes that only minimal
contributions will be required until 2008.
    Olin Corporation is a manufacturer concentrated in three business
segments: Metals, Chlor Alkali Products and Winchester. Metals
products include copper and copper alloy sheet, strip, foil, rod,
welded tube, fabricated parts, metal packages; and stainless steel and
aluminum strip. Chlor Alkali Products manufactures chlorine and
caustic soda, sodium hydrosulfite, hydrochloric acid and bleach
products. Winchester products include sporting ammunition, canister
powder, reloading components, small caliber military ammunition and
industrial cartridges.

    FORWARD-LOOKING STATEMENTS

    This communication includes forward-looking statements within the
meaning of the Private Securities Litigation Reform Act of 1995. These
statements relate to analyses and other information that are based on
management's beliefs, certain assumptions made by management,
forecasts of future results, and current expectations, estimates and
projections about the markets and economy in which we and our various
segments operate. The statements contained in this communication that
are not statements of historical fact may include forward-looking
statements that involve a number of risks and uncertainties.
    We have used the words "anticipate," "intend," "may," "expect,"
"believe," "should," "plan," "will," "estimate," and variations of
such words and similar expressions in this communication to identify
such forward-looking statements. These statements are not guarantees
of future performance and involve certain risks, uncertainties and
assumptions, which are difficult to predict and many of which are
beyond our control. Therefore, actual outcomes and results may differ
materially from those matters expressed or implied in such
forward-looking statements. We undertake no obligation to update
publicly any forward-looking statements, whether as a result of future
events, new information or otherwise. Relative to the dividend, the
payment of cash dividends is subject to the discretion of our Board of
Directors and will be determined in light of then-current conditions,
including our earnings, our operations, our financial conditions, our
capital requirements and other factors deemed relevant by our Board of
Directors. In the future, our Board of Directors may change our
dividend policy, including the frequency or amount of any dividend, in
light of then-existing conditions.
    The risks, uncertainties and assumptions involved in our
forward-looking statements, many of which are discussed in more detail
in our filings with the SEC, including our Annual Report on Form 10-K
for the year ended December 31, 2002, include, but are not limited to,
the following,:

    --  sensitivity to economic, business and market conditions in the
        United States and overseas, including economic instability or
        a downturn in the sectors served by us, such as automotive,
        electronics, coinage, telecommunications, ammunition, housing,
        vinyls and pulp and paper;

    --  extraordinary events, such as additional terrorist attacks or
        war with one or more countries;

    --  continued or additional economic and industry downturns that
        result in diminished product demand and excess manufacturing
        capacity in any of our segments and that, in many cases,
        result in lower selling prices and profits;

    --  the cyclical nature of our operating results, particularly
        declines in average selling prices in the chlor alkali
        industry and the supply/demand balance for our products,
        including the impact of excess industry capacity or an
        imbalance in demand for our chlor alkali products;

    --  an increase in our indebtedness or higher-than-expected
        interest rates, affecting our ability to generate sufficient
        cash flow for debt service;

    --  unforeseen effects of competition, including the migration by
        United States customers to low-cost foreign locations;

    --  costs and other expenditures in excess of those projected for
        environmental investigation and remediation or other legal
        proceedings;

    --  unexpected litigation outcomes or the impact of changes in
        laws and regulations;

    --  higher-than-expected raw material and utility or
        transportation and/or logistics costs;

    --  the occurrence of unexpected manufacturing interruptions and
        outages, including those occurring as a result of production
        hazards;

    --  unexpected additional taxes and related interest as the result
        of pending income tax audits; and

    --  the effects of any declines in global equity markets on asset
        values and any declines in interest rates used to value the
        liabilities in our pension plan.

    All of our forward-looking statements should be considered in
light of these factors. In addition, other risks and uncertainties not
presently known to us or that we consider immaterial could affect the
accuracy of our forward-looking statements.

    CONTACT: Olin Corporation, Norwalk
             Investor:
             Richard E. Koch, 203-750-3254
             Press:
             Thomas J. Fitzgerald, 203-750-3831